Condensed Consolidating Financial Information (Details 3) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Jun. 30, 2013	Jun. 30, 2012	Jun. 30, 2013	Jun. 30, 2012
Revenue:
Light building products	$ 118,035	$ 97,164	$ 279,501	$ 244,809
Heavy construction materials	75,114	74,728	197,286	189,105
Energy technology	3,881	3,729	10,804	8,766
Total revenue	197,030	175,621	487,591	442,680
Cost of revenue:
Light building products	82,096	66,558	202,723	176,501
Heavy construction materials	54,642	54,863	151,622	143,341
Energy technology	1,787	1,842	5,085	4,473
Total cost of revenue	138,525	123,263	359,430	324,315
Gross profit	58,505	52,358	128,161	118,365
Operating expenses:
Amortization	5,319	4,936	15,543	15,739
Research and development	1,786	2,280	5,209	5,750
Selling, general and administrative	28,215	29,212	79,308	76,186
Restructuring costs	0	0	0	2,145
Total operating expenses	35,320	36,428	100,060	99,820
Operating income	23,185	15,930	28,101	18,545
Other income (expense):
Net interest income (expense)	(11,111)	(15,975)	(32,722)	(41,958)
Other, net	24	57	262	(4,253)
Total other income (expense), net	(11,087)	(15,918)	(32,460)	(46,211)
Income (loss) from continuing operations before income taxes	12,098	12	(4,359)	(27,666)
Income tax benefit (provision)	(2,850)	2,030	(550)	(1,800)
Income (loss) from continuing operations	9,248	2,042	(4,909)	(29,466)
Income (loss) from discontinued operations, net of income taxes	1,768	(15,078)	1,793	(27,876)
Net income (loss)	11,016	(13,036)	(3,116)	(57,342)
Guarantor Subsidiaries
Revenue:
Light building products	118,035	97,164	279,501	244,809
Heavy construction materials	75,114	74,728	197,286	189,105
Energy technology	3,881	3,729	10,804	8,766
Total revenue	197,030	175,621	487,591	442,680
Cost of revenue:
Light building products	82,096	66,558	202,723	176,501
Heavy construction materials	54,642	54,863	151,622	143,341
Energy technology	1,787	1,842	5,085	4,473
Total cost of revenue	138,525	123,263	359,430	324,315
Gross profit	58,505	52,358	128,161	118,365
Operating expenses:
Amortization	5,319	4,936	15,543	15,739
Research and development	1,786	2,280	5,209	5,750
Selling, general and administrative	23,407	22,539	64,804	60,330
Restructuring costs				2,145
Total operating expenses	30,512	29,755	85,556	83,964
Operating income	27,993	22,603	42,605	34,401
Other income (expense):
Net interest income (expense)	9	(25)	(49)	(62)
Other, net	24	(268)	227	(6,603)
Total other income (expense), net	33	(293)	178	(6,665)
Income (loss) from continuing operations before income taxes	28,026	22,310	42,783	27,736
Income tax benefit (provision)	(7,170)	2,461	(9,240)	3,328
Income (loss) from continuing operations	20,856	24,771	33,543	31,064
Income (loss) from discontinued operations, net of income taxes	1,768	(15,078)	1,793	(27,876)
Net income (loss)	22,624	9,693	35,336	3,188
Parent Company
Operating expenses:
Selling, general and administrative	4,808	6,673	14,504	15,856
Total operating expenses	4,808	6,673	14,504	15,856
Operating income	(4,808)	(6,673)	(14,504)	(15,856)
Other income (expense):
Net interest income (expense)	(11,120)	(15,950)	(32,673)	(41,896)
Other, net		325	35	2,350
Total other income (expense), net	(11,120)	(15,625)	(32,638)	(39,546)
Income (loss) from continuing operations before income taxes	(15,928)	(22,298)	(47,142)	(55,402)
Income tax benefit (provision)	4,320	(431)	8,690	(5,128)
Income (loss) from continuing operations	(11,608)	(22,729)	(38,452)	(60,530)
Net income (loss)	$ (11,608)	$ (22,729)	$ (38,452)	$ (60,530)